you won't save a lot of time or effort changing what you're doing, but if you take your tumbler output after a few months and trnsfer it to a worm bin, they'll finish it off quite well in another few months

I won't recommend a 'stackable', as I don't think they're a serious alternative, but what a lot of folks use for an indoor [or balcony] worm bin is a Rubbermaid tote, [17 gallons is a good size], and with a bit of learning and practice, you may be able to replace your tumblers totally

Bill

squeeze,could you tell me why you think the stackable bins are not very good?I ordered one and then read your post,now i am courious,you seem to know a lot and i would value your opinion,maybe down the road i will change,this bin was pretty expencive,rubbermaid would certainly have been the cheaper way to go,other that that,what?thanks,just1more

to me the cost is one particular problem, the object of 'worming' really being to make better use of resources and reduce waste, but if you've got one, give it a try

commercial stackables I've seen are too small, and layers are too shallow - the larger the volume of material [to a reasonable point] the easier it is to manage food supply and moisture, and the less likely there is to be a problem because you "were just too busy [or sick, or gone, or ...] last week"

also, if you're interested in "fertilizer" output, the volume possible in a small scale stack doesn't seem worth the bother, although I'm not sure I understand the use of vermicompost in soilless growing, as the combination would result in loss of the benefits of the castings, the addition of humus and bacterial population, because compost isn't fertilizer, it's "soil conditioner"

for regular gardening [even container gardening, with soil], compost doesn't have to be real "finished", I regularly grow in pails filled with compost alone, and there are always recognizeable bits of veg matter in what I use from hot bins, but like I said, the tumbler output will make better worm system input, and getting a more uniform finished product might be faster in combination than the tumbler alone

Bill

This is a comparison of apples and oranges.
A compost tumbler with the right mix of greens and browns should produce hot, fast thermal compost using thermophile bacteria, where vermicomposting is cold composting (with redworms) at it's best.

Personally I think vermicompost is far richer in plant usable nutrients and active biology than finished thermal compost. I'm convinced that I see faster seed germination, stronger plants and higher yields using vermicompost.

Flow through systems can work very well by taking advantage of the simple fact that most worms will be living/eating in the upper layers - so bedding and feedstock is slowly added over time and the worms slowly migrate upwards in the system, leaving finished vermicompost behind. By the time the worms get to level 3 or higher, the lowest tier can be harvested.
Nothing says you have to drop a 'C' note on a commercial flow thru system - a few rubbermaid or sterlite bins and a drill with a 1/8" bit is all you really need to make such a system - google on "OSCR JR".
However, I would suggest that a newbie start out with a simple 10g or 18g bin and after achieving success with that, perhaps consider a flow thru system.

I have a problem with Bill's quote because compost isn't fertilizer, it's "soil conditioner"
It's both. Nature built nutrient rich, fertile top soil organically long before we developed petro-chemical NpK and called it 'fertilizer'. More simply, anything that makes soil more fertile is fertile-izer and manures (animal and green), compost and vermicompost all make soil more fertile.

well yes Dad, you can say that anything which increases "soil fertility" is a fertilizer, and certainly any compost can "increase fertility", but soil fertility is a balance of a lot of things, nutrients, minerals, organic matter, pH, tilth and structure, and microorganisms - compost provides the organic matter and microbes, but generally only very small amounts of NPK and maybe none of a number of the minor and trace nutrients, depending on what went into the compost mix - and having had quite a bit of compost lab tested, I can assure you the balance isn't what anyone would consider "fertilizer", and in fact the lab comparison of castings and hot compost showed little difference in nutritive composition, the primary difference being in microbial population

common useage defines a "fertilizer" as one or all of the major nutrients, NPK, and sometimes including the secondary nutrients calcium, sulfur, magnesium, and "complete fertilizers" will also include a wide range of micronutrients ... which is not to say that anyone needs "fertilizers" in a healthy soil

when soil-less or hydroponic culture is involved [what the original question implied], a specified "balanced" formula of nutrients is required, and compost won't meet the requirements as a "fertilizing" addition to the medium or nutrient solution

compost is generally considered a soil amendment or conditioner, and aside from it's addition to the humic makeup of the soil, the enhancement of soil microbiology is the biggest contribution it makes to soil fertility, compost additions help maintain soil health, which is all the fertility required

Bill

Well glad you have it straight Bill. The trouble with statements like that is it fuels the notion to the uninformed that petro-chemical NpK fertilizer is required to grow things.

Hi All! Just to clear up the term "fertilizer"

fer-til-iz-er n: one that fertilizes; a substance (as manure or a chemical mixture) used to make soil more fertile. Websters New Collegiate Dictionary (source)

larry

actually Larry, "fertilizers are compounds given to plants to promote growth" [sometimes by foliar application], soil fertility is a whole different thing, and "chemical mixtures" do nothing to improve soil fertility

Dad - I spend a lot of my composting education time trying to get chemical indoctrinated and dependent folks to accept that compost is NOT a fertilizer substitute, and that the way to "promote plant growth" is to focus on soil health ... pointing out that compost is not "fertilizer" is important when folks are used to using a teaspoon of 20-20-20 and expecting the same plant-centric "results" from dribs and drabs of compost

Bill

Thank you for sharing what you know and your valuable experiences. Excellent points made by everyone. Thank you abbeysdad. I appreciate the OSCR referral, too.

I searched for comparative studies on the qualitative differences of household compost and vermicastings and vermicompost after I posted my questions and waited for replies and reviews. Data and analyses do support what you both said. Weighing the labor and costs output with the quality of vermicastings and compost (vs my compost from cold composting I'm doing), there is value in making an effort to make and take care of worm bins. I will have to brainstorm and find out how to maintain the ideal temperature range outdoors in all four seasons, however. I also will make my own tumbler at a later point if time, space, and resources allow since I saw an easy to make floor model at my local garden center yesterday.

In my hybrid soilless and hydroponic setup, my primary objective of using vermicompost isn't to feed my container soil. I will use purchased vermicastings (w/processed manurer) and homemade vermicompost (w/o) for all the benefits you mentioned such as a potting mix amendment to improve short-term physical structure, a mulch to supply some temperature/moisture control, initiation of beneficial microbial activities for disease suppression, and for needed supplemental nitrogen, calcium, and other micronutrients from organic sources.

What are the most energy efficient, safe, and best ways to maintain worm bins at room temperatures in the winter and in the summer on a semi-exposed balcony? And the associated pros and cons?

Flooding will not likely be an issue since only one side of the balcony is exposed, and the balcony floor only gets wet half to 3/4 way in during downpours. As far as I can see, I need to have temp control of 50-80 F for the worm bins in a local climate of 25-100+ F. True?